Subtract 12/20 from 3/81
3/81 - 12/20 is -76/135.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 20 is 1620
Next, find the equivalent fraction of both fractional numbers with denominator 1620 - For the 1st fraction, since 81 × 20 = 1620,
3/81 = 3 × 20/81 × 20 = 60/1620 - Likewise, for the 2nd fraction, since 20 × 81 = 1620,
12/20 = 12 × 81/20 × 81 = 972/1620 - Subtract the two like fractions:
60/1620 - 972/1620 = 60 - 972/1620 = -912/1620 - After reducing the fraction, the answer is -76/135
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